Particularly in light of Carrier Aggregation (CA) schemes supported by modern cellular communications networks, wireless devices, such as mobile phones, typically support multiple frequency bands. Support for multiple frequency bands is provided by multiple radio front-ends, each supporting one or more frequency bands. The radio front-ends are connected to a common antenna via a multiplexer (e.g., a diplexer for the dual-band scenario or a triplexer for a tri-band scenario). In addition, in order to support Multiple-Input-Multiple-Output (MIMO) operation, wireless devices may also include an additional antenna(s) along with a corresponding multiplexer(s) and radio front-end(s).